a. Field of the Invention
The invention relates to a light guide plate and a backlight module with the light guide plate.
b. Description of the Related Art
FIG. 1 shows a three-dimensional diagram of a conventional backlight module 20. Referring to FIG. 1, the backlight module 20 has a back plate 21. A light guide plate 22, a reflective sheet 23, a light source 24, and a set of optical films such as a diffuser 25 and a brightness enhancement film 26 are disposed in the back plate 21. The diffuser 25 is adjacent to a light-emitting side of the light guide plate 22, the reflective sheet 23 is adjacent to a bottom surface 22a of the light guide plate 22, and the light source 24 is adjacent to a light incident side of the light guide plate 22. The light guide plate 22 is a transparent substrate and guides light beams emitted from the light source 24. The light beams enter the light guide plate 22 from the light incident side of the light guide plate 22, leave the light guide plate 22 via a top surface (light-emitting side) of the light guide plate 22, and passes the diffuser 25 and the brightness enhancement film 26 in succession to improve output luminance and illumination uniformity of the backlight module 20. In conventional designs, micro structures are formed on the bottom surface 22a of the light guide plate 22 to improve the illumination uniformity of the backlight module 20. For example, Taiwan patent no. TWI294402 discloses an optics made by micro droplet inkjet, wherein micro structures are formed by micro droplets falling on a surface of a transparent substrate. Besides, Taiwan patent no. TWM345244 discloses a light guide plate, where a bottom surface of the light guide plate is an ink layer and semi-spherical patterns are formed as micro structures on the surface of the ink layer. Further, Taiwan patent publication no. 200732785 discloses a fabrication process of forming micro bumps on a light guide plate by inkjet or dispensing process.
However, the configurations of micro structures disclosed in the above designs fail to provide an effective mechanism allowing to regionally adjust output luminance of a light guide plate. Hence, the illumination uniformity of the light guide plate may not be further improved.